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arXiv · 2402.09680

Tradeoff relations in open quantum dynamics via Robertson, Maccone-Pati, and Robertson-Schr\"odinger uncertainty relations

Tomohiro Nishiyama·Yoshihiko Hasegawa
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Abstract

The Heisenberg uncertainty relation, together with Robertson's generalisation, serves as a fundamental concept in quantum mechanics, showing that noncommutative pairs of observables cannot be measured precisely. In this study, we explore the Robertson-type uncertainty relations to demonstrate their effectiveness in establishing a series of thermodynamic uncertainty relations and quantum speed limits in open quantum dynamics. The derivation utilises a scaled continuous matrix product state representation that maps the time evolution of the quantum continuous measurement to the time evolution of the system and field. Specifically, we consider the Maccone-Pati uncertainty relation, a refinement of the Robertson uncertainty relation, to derive thermodynamic uncertainty relations and quantum speed limits. These newly derived relations, which use a state orthogonal to the initial state, yield bounds that are tighter than previously known bounds. Moreover, we consider the Robertson-Schr\"odinger uncertainty, which extends the Robertson uncertainty relation. Our findings not only reinforce the significance of the Robertson-type uncertainty relations, but also expand its applicability in identifying uncertainty relations in open quantum dynamics.

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Tomohiro Nishiyama, Yoshihiko Hasegawa. 2024-02-15. Tradeoff relations in open quantum dynamics via Robertson, Maccone-Pati, and Robertson-Schr\"odinger uncertainty relations. https://doi.org/10.1088/1751-8121/ad79cd

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